Lateral line pathways and connections are being studied by silver axonal degeneration, radioautographic and horseradish peroxidase methods in the clearnose skate, Raja eglanteria. Emphasis is being given to the differential central projections of neurons that carry information from the electroreceptors (ampullae of Lorenzini) and mechanoreceptors (neuromast organs). Thus far, it has been shown that these two functional components of the lateral line system have separate pathways and terminal fields at medullary and mesencephalic levels. Work currently in progress is designed to elucidate projections to the dorsal thalamus and to determine whether there are thalamic efferent projections to specialized cell populations of the telencephalon.